1. Field of the Invention
The present invention relates to an image forming device to which an optional unit such as a paper feeder (PF) can be attached as an extension unit. Examples of the image forming device include a copying machine and a printer.
2. Description of the Related Art
Image forming devices such as a copying machine and a printer form an image on paper based on electrophotography. According to such image forming devices, an electrostatic latent image is formed on an image carrier such as a photoconductive drum. This electrostatic latent image is developed by a developing device using a toner which is a developer.
In this way, the electrostatic latent image is visualized as a toner image. This toner image on the image carrier is transferred to paper using transfer equipment such as a transfer roller. Then, the paper, to which the toner image was transferred, is transported to a fixing device. The toner image is heated and pressurized by this fixing device. The toner image is then fixed to the paper. The paper, to which the toner image was fixed, is discharged outside the image forming device. In this way, an image forming process is completed.
Some types of the image forming device can accommodate an optional unit such as a paper feeder (PF) which is attached to the image forming device based on a user's needs. When the optional unit is a paper feeder, the image forming device is connected to the paper feeder by stacking the image forming device onto the paper feeder which is placed on a floor. In addition, a connector electrically connects the image forming device with the paper feeder.
Incidentally, when the connector is provided on a bottom surface of the image forming device, a tracking phenomenon may occur after a line is connected, due to dust that has accumulated on the connector. A possible solution to this type of problem is to provide a connector cover which opens and closes a connecting surface of the connector, and to keep the connecting surface of the connector closed with the connector cover when the connector is not used. In this case, the connector cover is opened after the image forming device is connected to the paper feeder and the like. Then, the connecting surface of the connector is opened, and thus the image forming device and the paper feeder are electrically connected.
Japanese Published Patent No. H7-295319 (hereinafter, referred to as “Related Art Document 1”), for example, discloses a configuration regarding the connection between an image forming device and an optional unit. According to Related Art Document 1, a connector is provided on at least one of the image forming device or the optional unit. As the locations of the image forming device and the optional unit are determined and the connection between the image forming device and the optional unit is made, this connector is moved to a position at which the connection is made (i.e., the “connecting position”). This connector is connected to another connector provided on the other device.
In addition, Japanese Unexamined Utility Model Application, First Publication No. H6-23946 (hereinafter, referred to as “Related Art Document 2”) discloses a configuration in which a positioning pin is provided at a frontal portion of a bottom surface of an image forming device. An optional unit is attached from the lower side of this image forming device. This optional unit is a bottom cassette holder. On the upper surface of this optional unit, a positioning guide is provided. The positioning guide includes a V-shaped notch, which leads the positioning pin at the frontal portion of the image forming device toward the notch. Thus, the positioning pin is received and is latched at the bottom part of the notch in the frontal side at the matching position.
Thus, according to one of the configurations described above, the connector is opened and closed by the connector cover. However, even if this configuration is applied, the connector cover may be kept open when the image forming device is not connected to an optional unit such as a paper feeder. In other words, when the connector provided on the image forming device is not used, the connector cover may be left open. In such cases, dust may accumulate on the connector, and a tracking phenomenon may be triggered.
Furthermore, when the image forming device is connected to the optional unit such as a paper feeder, the guiding pin provided on the optional unit may hit the connector provided on the image forming device. As a result, a crack may be formed on the connector housing, which may cause glitches such as abnormal heating. Neither Related Art Document 1 nor Related Art Document 2 provides a configuration that deals with dust accumulating on the connector. In addition, the guiding pin contacting the connector remains to be an unsolved problem. Considering the problems described above, the present invention aims to provide an image forming device such that a connector cover shuts and protects a connecting surface of a connector when the optional unit is not attached to the image forming device, and when the optional unit is attached to the image forming device, the connecting surface of the connector is opened in accordance with a connecting operation of the optional unit, thus providing an electrical connection with the optional unit.